Rational design of flower-like cobalt–manganese-sulfide nanosheets for high performance supercapacitor electrode materials†
The design and development of composite materials with novel structures is one of the effective ways to enhance the electrochemical properties of supercapacitors. In this paper, a one-step electrodeposition method is used to adjust the morphology and structure of CoMnS nanomaterials by changing the amount of CS2. CoMnS nanomaterials with unique flower-like structures are reasonably prepared, which promotes the flow of electron transfer and improves the electrochemical behavior. It is worth noting that when the amount of CS2 is 4 mmol, the specific capacitance of CoMnS-4 reaches 3469.5 F g−1 at 1 A g−1, and the specific capacitance is still 2830.5 F g−1 (maintaining 81.56%) until the high current density reaches 20 A g−1. After 10 000 cycles, it shows excellent cycle stability (maintaining 95.78% at 20 A g−1). The CoMnS-4//AC asymmetric supercapacitor device has an excellent energy density of 85.91 W h kg−1 when the power density is 800 W kg−1, which shows it's great application value.